Recovery and nonrecovery of the untrained state in an exchange-coupled system

TY - JOUR

T1 - Recovery and nonrecovery of the untrained state in an exchange-coupled system

AU - Jutimoosik, Jaru

AU - Yimnirun, Rattikorn

AU - Setzer, Annette

AU - Esquinazi, Pablo

AU - Stahn, Jochen

AU - Paul, Amitesh

N1 - Publisher Copyright: © 2015 American Physical Society.

PY - 2015/6/25

Y1 - 2015/6/25

N2 - We report depth sensitive investigations of the magnetic interaction between exchange-coupled stacked CoO and ferromagnetic Co bilayers (separated by thick Au layers) as we explore the degree of recovery of the untrained state after the first two field cycles. Such a recovery is expected by field cycling a reorientation field (HRE) along a direction (ΩRE) away from the initial field cooling direction. Measurements as a function of ΩRE and the strength of HRE (along each direction) map the influence of ΩRE on the reversal mechanism in the layers and thereby the degree of recovery. Our results are consistent with the earlier observations in similar systems that was realized with ΩRE=90. We ascribe these partial and/or significant recoveries to the unchanged sense of rotation after initial field cooling of the ferromagnetic magnetization upon each field cycling. Furthermore, in our system, we find that this recovery can be regulated by choosing various other HRE and ΩRE values without changing the rotational sense. The best recipe for recovery is identified for ΩRE=45, that can be achieved partially with HRE=3.0 kOe and remain significant even with HRE=10.0 kOe. In this study we not only understand the fundamental mechanism in the recovery of training, but also instigate its technological prospects by lifting the directional restrictions of the reorientation field.

AB - We report depth sensitive investigations of the magnetic interaction between exchange-coupled stacked CoO and ferromagnetic Co bilayers (separated by thick Au layers) as we explore the degree of recovery of the untrained state after the first two field cycles. Such a recovery is expected by field cycling a reorientation field (HRE) along a direction (ΩRE) away from the initial field cooling direction. Measurements as a function of ΩRE and the strength of HRE (along each direction) map the influence of ΩRE on the reversal mechanism in the layers and thereby the degree of recovery. Our results are consistent with the earlier observations in similar systems that was realized with ΩRE=90. We ascribe these partial and/or significant recoveries to the unchanged sense of rotation after initial field cooling of the ferromagnetic magnetization upon each field cycling. Furthermore, in our system, we find that this recovery can be regulated by choosing various other HRE and ΩRE values without changing the rotational sense. The best recipe for recovery is identified for ΩRE=45, that can be achieved partially with HRE=3.0 kOe and remain significant even with HRE=10.0 kOe. In this study we not only understand the fundamental mechanism in the recovery of training, but also instigate its technological prospects by lifting the directional restrictions of the reorientation field.

UR - http://www.scopus.com/inward/record.url?scp=84934300095&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.91.224428

DO - 10.1103/PhysRevB.91.224428

M3 - 文章

AN - SCOPUS:84934300095

VL - 91

JO - Physical Review B

JF - Physical Review B

SN - 2469-9950

IS - 22

M1 - 224428

ER -